Backup on Secondary HDD

I have an additional hdd connected to my server PC.
Now I want the backup in ispconfig to be stored in the secondary hard disk instead of the primary hard disk itself. So in case the primary hdd fails, I can restore the server from the secondary hard disk.
How I can mount the secondary hard disk and give the path for that so that back up is stored on the secondary hdd?

I don't know till, but I have not created the mount point and it was being created automatically for example - /media/storage.
So The storage folder was being created but halting on boot.
What I have done deleted that folder and created another with sudo mkdir /media/server-backup and modified the /etc/fstab accordingly.
Now it it booting correctly and mounting the secondary hdd.
One Last question in system > server config - there is a checkbox - backup directory is a mount?
I understand that this checkbox should be checked?
Thanks.